中国地理科学 ›› 2017, Vol. 27 ›› Issue (4): 539-551.doi: 10.1007/s11769-017-0886-6

• 论文 • 上一篇    下一篇

Effects of Environmental Conditions and Aboveground Biomass on CO2 Budget in Phragmites australis Wetland of Jiaozhou Bay, China

GAO Manyu, KONG Fanlong, XI Min, LI Yue, LI Jihua   

  1. College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
  • 收稿日期:2016-05-25 修回日期:2016-09-22 出版日期:2017-08-27 发布日期:2017-06-30
  • 通讯作者: XI Min.E-mail:ximin@qdu.edu.cn E-mail:ximin@qdu.edu.cn
  • 基金资助:

    Under the auspices of National Natural Science Foundation of China (No. 41101080), Shandong Natural Science Foundation of China (No. ZR2014DQ028, ZR2015DM004)

Effects of Environmental Conditions and Aboveground Biomass on CO2 Budget in Phragmites australis Wetland of Jiaozhou Bay, China

GAO Manyu, KONG Fanlong, XI Min, LI Yue, LI Jihua   

  1. College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
  • Received:2016-05-25 Revised:2016-09-22 Online:2017-08-27 Published:2017-06-30
  • Contact: XI Min.E-mail:ximin@qdu.edu.cn E-mail:ximin@qdu.edu.cn
  • Supported by:

    Under the auspices of National Natural Science Foundation of China (No. 41101080), Shandong Natural Science Foundation of China (No. ZR2014DQ028, ZR2015DM004)

摘要:

Estuarial saline wetlands have been recognized as a vital role in CO2 cycling. However, insufficient attention has been paid to estimating CO2 fluxes from estuarial saline wetlands. In this study, the static chamber-gas chromatography (GC) method was used to quantify CO2 budget of an estuarial saline reed (Phragmites australis) wetland in Jiaozhou Bay in Qingdao City of Shandong Province, China during the reed growing season (May to October) in 2014. The CO2 budget study involved net ecosystem CO2 exchange (NEE), ecosystem respiration (Reco) and gross primary production (GPP). Temporal variation in CO2 budget and the impact of air/soil temperature, illumination intensity and aboveground biomass exerted on CO2 budget were analyzed. Results indicated that the wetland was acting as a net sink of 1129.16 g/m2during the entire growing season. Moreover, the values of Reco and GPP were 1744.89 g/m2 and 2874.05 g/m2, respectively; the ratio of Reco and GPP was 0.61. Diurnal and monthly patterns of CO2 budget varied significantly during the study period. Reco showed exponential relationships with air temperature and soil temperature at 5 cm, 10 cm, 20 cm depths, and soil temperature at 5 cm depth was the most crucial influence factor among them. Meanwhile, temperature sensitivity (Q10) of Reco was negatively correlated with soil temperature. Light and temperature exerted strong controls over NEE and GPP. Aboveground biomass over the whole growing season showed non-linear relationships with CO2 budget, while those during the early and peak growing season showed significant linear relationships with CO2 budget. This research provides valuable reference for CO2 exchange in estuarial saline wetland ecosystem.

关键词: net ecosystem CO2 exchange, ecosystem respiration, gross primary production, influencing factor, estuarial saline reed wetland, static chamber-GC method

Abstract:

Estuarial saline wetlands have been recognized as a vital role in CO2 cycling. However, insufficient attention has been paid to estimating CO2 fluxes from estuarial saline wetlands. In this study, the static chamber-gas chromatography (GC) method was used to quantify CO2 budget of an estuarial saline reed (Phragmites australis) wetland in Jiaozhou Bay in Qingdao City of Shandong Province, China during the reed growing season (May to October) in 2014. The CO2 budget study involved net ecosystem CO2 exchange (NEE), ecosystem respiration (Reco) and gross primary production (GPP). Temporal variation in CO2 budget and the impact of air/soil temperature, illumination intensity and aboveground biomass exerted on CO2 budget were analyzed. Results indicated that the wetland was acting as a net sink of 1129.16 g/m2during the entire growing season. Moreover, the values of Reco and GPP were 1744.89 g/m2 and 2874.05 g/m2, respectively; the ratio of Reco and GPP was 0.61. Diurnal and monthly patterns of CO2 budget varied significantly during the study period. Reco showed exponential relationships with air temperature and soil temperature at 5 cm, 10 cm, 20 cm depths, and soil temperature at 5 cm depth was the most crucial influence factor among them. Meanwhile, temperature sensitivity (Q10) of Reco was negatively correlated with soil temperature. Light and temperature exerted strong controls over NEE and GPP. Aboveground biomass over the whole growing season showed non-linear relationships with CO2 budget, while those during the early and peak growing season showed significant linear relationships with CO2 budget. This research provides valuable reference for CO2 exchange in estuarial saline wetland ecosystem.

Key words: net ecosystem CO2 exchange, ecosystem respiration, gross primary production, influencing factor, estuarial saline reed wetland, static chamber-GC method